How Do Forced Air Heaters Work?
Forced air heating systems are among the most common methods used to heat homes, offering efficient and reliable performance during chilly seasons.
Whether the heat source for your system is powered by gas or electricity, these systems work on similar principles: they heat air and distribute it throughout your home via a ductwork system.
Understanding how forced air heaters work can help you maintain them effectively, troubleshoot problems, and maximize their lifespan.
Let’s look at how these systems function and provide some essential troubleshooting tips and maintenance advice.
KEY TAKEAWAYS
- Forced air heating systems, whether powered by gas or electricity, work by heating air and distributing it through a home's ductwork. Gas furnaces ignite fuel to heat air, while electric systems often use heat pumps, which transfer heat from outside air or the ground indoors. In colder conditions, electric systems may rely on auxiliary heating elements to maintain warmth.
- Common problems like a furnace not starting or inadequate heating can often be addressed through basic troubleshooting steps. These include checking thermostat settings, ensuring circuit breakers are functioning, and inspecting air filters. More complex issues, such as leaky ducts or motor problems, typically require professional repair services.
- Regular maintenance, such as replacing air filters, cleaning ductwork, and scheduling annual professional inspections, is crucial to ensure efficiency, improve air quality, and extend the lifespan of the heating system. Professional services can identify and resolve potential issues before they escalate, reducing energy costs and improving system performance.
How Forced Air Heaters Work
Gas Forced Air Heating Systems
Gas furnaces are a popular choice due to their efficiency and ability to heat homes quickly. Here's how they operate:
- Ignition and Heating: A gas furnace uses natural gas or propane as fuel. The system's thermostat triggers the furnace to ignite the burners. This process generates heat in the heat exchanger.
- Air Circulation: A blower fan pushes cool air from your home over the heat exchanger, warming the air.
- Distribution: The heated air blown through the furnace heat exchanger is distributed through a network of ducts to heat your home.
Electric Forced Air Heating Systems
Electric forced air heaters work similarly to gas furnaces but rely on electricity to produce heat.
Most electric forced air heating systems use a heat pump system to heat your home. (The same heat pump system also cools your home during summer.)
During winter, heat pumps work by extracting heat from outside air (or the ground, in geothermal systems) and transferring it indoors via a sealed refrigerant system. Heat pumps also use an electric heating element to heat your home in extremely cold weather when the sealed refrigerant system can’t efficiently provide enough heat for your home.
Here’s how a heat pump works in a forced air heating system:
- The refrigerant absorbs heat from the air outside, turning into a gas.
- The compressor raises the pressure and temperature of the refrigerant.
- The hot refrigerant flows through the indoor evaporator heat exchanger, releasing heat to warm your home as the blower fan circulates air through the evaporator and throughout the house.
- The refrigerant cools down and returns to the outdoor unit to repeat the process.
When outside temperatures drop below 30 degrees, the electric heating element kicks in as needed to help heat your home.
Troubleshooting Common Forced Air Heating Issues
Follow these expert troubleshooting tips to resolve common problems with your forced air heating system.
Furnace Won’t Turn On
Gas Furnace
These basic troubleshooting tips may help you get your furnace working again:
- Check that the thermostat is set to "heat" and the temperature setting is set high enough so the control will start the furnace.
- Check the house circuit breakers for your furnace and reset any tripped circuit breakers.
- Check the emergency shutoff switch for the furnace. It might be at the entrance to the furnace closet, at the top of the basement stairs, or on the furnace. It might have a red switch plate. If someone switched it off or your turned the switch off for summer and forgot to turn it back on in the fall, the furnace won't work.
- Verify that the gas supply shut-off valve for the furnace is open.
If these basic troubleshooting tips don’t help, you’ll likely need to schedule furnace repair service to have a technician examine your heating system and fix the problem.
Electric Heat Pump System
- Check that the thermostat is set to "heat" and the temperature setting is set high enough so the control will start the heat pump.
- Check the house circuit breakers for your heat pump system and reset any tripped breakers.
If these tips don’t help, you’ll likely need to schedule heating system repair to have a service technician examine your heat pump and fix the problem.
Inadequate Heating
Possible causes of inadequate heating include:
- Clogged air filter.
- Leaky air ducts.
- Bad indoor blower motor.
Check the heating system air filter first. Replace the filter if you find it clogged with dust.
Leaky air ducts or a bad indoor blower motor are problems that will typically need to be resolved by a contractor or service technician.
Maintenance Tips to Keep Your Heating System Running Smoothly
Proper maintenance is crucial for extending the life of your forced air heater and maintaining its efficiency. Here’s how to stay proactive:
Replace Air Filters Regularly
Dirty air filters restrict airflow, forcing your system to work harder. Replace them every 1-3 months, depending on usage and according to the guidelines in your owner’s manual.
Clean the Ductwork
Dust and debris can accumulate in your ducts, reducing airflow and spreading allergens.
Schedule professional HVAC air duct cleaning every 3-5 years or more frequently if you have pets or allergies.
Schedule Annual Professional Inspections and Maintenance
Professional heating system tune-ups will help your forced air heater to run smoothly and can identify potential issues before they become costly repairs.
Annual Gas Furnace Maintenance
Scheduling annual professional furnace cleaning and maintenance service offers numerous benefits. It ensures your furnace stays in top condition, contributing to safer and more efficient heating performance.
Sears Home Services technicians have the expertise and experience to thoroughly clean your furnace. They are trained to identify and remove dirt, dust, and debris, improving air quality in your home and reducing respiratory issues.
Professional cleaning services also enhance your heating system's performance and efficiency. Dirt and debris buildup forces your furnace to work harder and consume more energy. Removing these obstructions helps your furnace operate more efficiently, leading to lower energy bills and a reduced carbon footprint. View this YouTube video to learn more about professional furnace maintenance by Sears Home Services:
Heat Pump Maintenance
Scheduling annual preventive maintenance and cleaning for your heat pump is essential for smooth and efficient heating system operation.
During annual heat pump maintenance and cleaning service, our technician will:
- Check your control thermostat settings and review the settings with you.
- Check the air filter.
- Check electrical connections.
- Make sure the system controls and safety circuits work properly.
- Lubricate the blower motor, if necessary.
- Check the condenser coil and clean it, if needed.
- Check and clean the condensate drain line.
- Check the evaporator for adequate air flow.
In addition to helping your heat pump run smoothly and efficiently, annual professional maintenance will help keep your system lasting longer.
The Importance of Home Warranty Plans
Even with regular maintenance, heating systems can experience unexpected breakdowns. A home warranty plan can provide peace of mind by covering repair and replacement costs for critical components. If your system is aging or you’re concerned about repair expenses, investing in a warranty can save you from hefty bills.
Keep your forced air heating system in top shape with the help of Sears Home Services. We know heating systems and our experienced technician can help you with top-notch maintenance and repairs.
We’ll help you keep your home warm and cozy all winter long.
Schedule your HVAC maintenance now!
HVAC checkups from Sears Home Services help keep your heating and cooling system running at its best. Prevent costly repairs and can make your HVAC system more energy efficient with routine maintenance.
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Maintain HVAC Resources
Discover how the condenser works in a central air conditioner system and how to maintain it.
Learn how a mini-split heat pump system works and how to maintain it.
Learn how electric heaters work in central air conditioning systems and heat pumps to heat your home in winter.
Learn how an HVAC compressor works in a home cooling system.
Glossary Terms
A humidifier is a device designed to increase humidity levels in a single room or an entire building, improving air quality and comfort.
Swamp cooling, also known as evaporative cooling, is a method that cools air through the natural process of water evaporation. It is energy-efficient and environmentally friendly, particularly effective in hot, dry climates.
Freon is a trade name for a group of chlorofluorocarbons (CFCs) used as refrigerants in air conditioning and refrigeration systems, known for its role in ozone depletion.
An inverter AC unit is an air conditioning system equipped with inverter technology that allows it to vary the compressor speed, enabling precise temperature control and increased energy efficiency.
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